gmt-fork/doc/rst/source/explain_-icols_full.rst_

.. _-icols_full:

**-i**\ *cols*\ [**+l**][**+s**\ *scale*][**+o**\ *offset*][,\ *...*][,\ **t**\ [*word*]]
    Select specific data columns for primary input, in arbitrary order. Columns
    not listed will be skipped. Give individual columns (or column ranges
    in the format *start*\ [:*inc*]:*stop*, where *inc* defaults to 1 if
    not specified) separated by commas [Default reads all columns in order,
    starting with the first column (0)]. Columns may be repeated.  To each
    column, optionally add any of  the following: **+l** takes **log10** of
    the input values first; **+s**\ *scale*, subsequently multiplies by a
    given  scale factor [1]; **+o**\ *offset*, finally adds a given offset [0].
    To read from a given column until the end of the record, leave off *stop*.
    Normally, any trailing text is read but when **-i** is used you must explicitly add
    the column **t** to retain the text. To only ingest a single word from the
    trailing text, append the word number (first word is 0).  Finally, **-in**
    will simply read the numerical input and skip any trailing text.